Hydrothermal Deposition and Further Simulative Optimization of Device Achieving Efficiency Close 19% for AgSbS₂ Solar Cell

Abstract As an emerging light‐absorbing material, AgSbS₂ attracts attention due to its excellent water and oxygen stability, environmental benign elemental composition, and high absorption coefficient. However, the reported highest power conversion efficiency (PCE) of AgSbS₂ solar cell is only 2.25% due to the lack of suitable AgSbS₂ thin film preparation strategy and systematic materials investigation toward improving the physical properties. Here a hydrothermal deposition method is developed for the fabrication of AgSbS₂ films, which show large grain size and compact surface morphology. Planar heterojunction device structure is applied with improved electrical contact and carrier transport between the electron layer/light absorbing layer, which generates a PCE of 3.39%, representing the highest efficiency of this material. To explore the performance optimization direction of AgSbS₂ photovoltaic devices, the device is numerically simulated. Finally, it is found that the PCE of AgSbS₂ solar cells can reach 18.99% in theory, and the improvement of crystallinity and interface recombination state are the key methods to elevate its efficiency, which provides reference for the preparation of high‐quality AgSbS₂ film and further improvement of PCE.